Senior Software Engineer

Saef BV; Amstelveen; On-site; EUR 75,000 - 110,000; Full time

Benefits offered by this job

Travel expenses covered

Company laptop

Job summary

Saef is building the new protection standard for luxury watches. The Senior Software Engineer will own the app feature set end to end, collaborating with hardware and cloud teams to ship secure, demo-ready releases. You’ll work in a small, senior team with real ownership, not a management layer above engineers.

You’ll design, build, and ship core app features, integrate the app with hardware and the cloud backend, and iterate quickly with release cycles while maintaining product readiness.

Qualifications

• 5+ years shipping production mobile apps.
• Proficiency with Swift, Kotlin, Flutter, or React Native.
• Experience integrating with hardware via BLE and cloud services.
• Security by design mindset and privacy focus.
• Comfort in a small, in-person, high-trust team.

Responsibilities

• Design, build, and ship core app features end to end.
• Integrate the app with hardware (BLE) and cloud backend.
• Iterate alongside web and hardware release cycles.
• Make pragmatic architecture calls for scalable product.
• Protect wearer data with security-first design.

Skills

Mobile app development

Swift/Kotlin

Flutter/React Native

Backend languages

BLE hardware integration

Cloud services

Security mindset

Job description

Own the app at Saef, the part of the product every customer touches.

The role

The Saef app is how someone confirms, from a hotel room in another country, that the most valuable object they own is safe. As Senior Software Engineer at Saef, you own the app feature set end to end. You’ll work alongside the senior web developer and the hardware team, iterating in parallel with hardware and cloud releases. This is a hands‑on senior role with real ownership, not a management layer above other engineers.

What you’ll do

• Design, build, and ship core app features end to end
• Integrate the app with hardware (firmware, BLE connectivity) and the cloud backend
• Iterate quickly alongside web and hardware release cycles, keeping the product demo-ready at all times
• Make pragmatic architecture calls and help freeze a stable product architecture as the team scales
• Build with security and privacy by design; protecting wearer data is treated as an existential priority

What we’re looking for

• 5+ years shipping production mobile applications to real users
• Proficiency with modern mobile development: native (Swift / Kotlin) or cross‑platform (Flutter / Dart or React Native), plus a modern backend language such as TypeScript/Node, Python, or Go
• Comfort working close to hardware: BLE, device pairing, real‑time data
• Cloud fluency enough to integrate cleanly with platform services
• A bias toward shipping over debating, paired with sound engineering judgment
• Effective in a small, in‑person, high‑trust team

Nice to have

• Experience in consumer hardware, wearables, or IoT
• Exposure to luxury, premium, or trust‑sensitive products
• Interest in on‑device ML or edge computing

What you'll get

• Real responsibility from day one in a small, senior team
• Ownership of the firmware at the core of the product
• Travel expenses covered
• Company laptop

About Saef

Saef is building the new protection standard for luxury watches. Invisible, always‑on hardware goes into the watch. A phone app tells the owner where it is and that it’s safe. We’re a small, senior team of engineers and designers that treats this as a system‑level problem: hardware, software, security, and trust, all built together. We’re launching with select partners, with beta planned in 2027. We can demo a real working product at any stage of development. That’s not a tagline. It’s how we work.

Please note

Candidates must have valid authorization to work in the Netherlands (e.g., EU/EEA nationality, a valid work permit, or a residence permit that includes work rights). We are unable to sponsor visas for this role.